LTC3454

• Product introduction

LTC34541A synchronous buck-boost high currentLED drivers

peculiarity

• High efficiency: 90% typical in flashlight mode >, >80% in flash mode
• Wide V_INRange: 2.7V to 5.5V
• Up to 1A continuous output current
• 3.5% LED current setting accuracy
• Internal soft start
• LED open/short circuit protection
• 1MHz constant frequency operation
• Zero downtime current
• Overtemperature protection
• Small form factor, thermally enhanced 10-pin (3mm x 3mm) DFN package

• description

  LTC^®The 3454 is a synchronous buck-boost DC/DC converter optimized for driving a single high-power LED from a single Li-Ion battery input at up to 1A. Depending on the input voltage and LED forward voltage, the regulator can operate in synchronous buck, synchronous boost, or buck-boost mode. Achieves greater than 90% PLED/PIN efficiency over the entire usable voltage range (2.7V to 4.2V) of a single Li-Ion battery.

  Two external resistors and two enable inputs can be used to set the LED current to one of four values, including shutdown. In shutdown mode, no supply current is consumed.

  The high constant operating frequency of 1MHz allows the use of small external components. The LTC3454 is available in a low profile (only 0.75mm height) thermally enhanced 10-lead (3mm × 3mm) DFN package.

• apply

  • Take a photo phone flash
  • Cellular phone flashlight lighting
  • Digital cameras
  • PDA
  • Various lithium-ion battery LED drivers